Key learning points

1. You can calculate the scale factor from the two areas.
2. Having calculated the scale factor, you can find missing lengths.

Keywords

• Similar - Two shapes are similar if the only difference between them is their size. Their side lengths are in the same proportions.

• Invariant - A property of a shape is invariant if that property has not changed after the shape is transformed.

• Enlargement - Enlargement is a transformation that causes a change of size.

• Scale factor - A scale factor is the multiplier between similar shapes that describes how large one shape is compared to the other.

Common misconception